Plochionocerus igneus ( Fauvel, 1901 )

Asiain, Julieta, Márquez, Juan & Morrone, Juan J., 2007, Phylogenetic systematics of the genera Plochionocerus Dejean and Agrodes Nordmann (Coleoptera: Staphylinidae: Xantholinini), Zootaxa 1584, pp. 1-53 : 19-20

Plochionocerus igneus ( Fauvel, 1901)

Sterculia ignea Fauvel, 1901: 252 ; Herman, 2001: 3745 ( Plochionocerus ).

Sterculia magnifica Bernhauer, 1911: 412 ; Herman, 2001: 3745 ( Plochionocerus ), syn. nov.

Type material (2 specimens). Holotype of Sterculia ignea , male: “Amazonas / ignea Fvl. / R. I. Sc. N. B. 17.479 Coll. et det. A. Fauvel / Type ” ( IRSNB). Holotype of Sterculia magnifica , female: “Obidos, 1904, P. Leconte / 4010 / magnifica Brh. Typus / Chicago NHMus M. Bernhauer Collection” ( FMNH).

Additional material (20 specimens). BRAZIL: Pará, Redencao vic., Kayapo Territory, Pinkaiti Field Station on Riozinho R., 7°43.83’S, 52°02.16’W, 23–28.XI.1998, logged gaps near, tropical evergreen seasonal lowland forest on clay soil, dung pitfall or flight intercept traps, P. Y. Scheffler ( FMNH, Ψ, ɗ); Rio Tapajoz, Amazonas, J. F. Zikán ( FMNH, ɗ); Rio Yurná, Est. Amaz., 1901, Shering (CC-UAEH, ɗ); Barcillos, Rio Negro, Amaz., 30.VIII.1927, J. F. Zikán ( FMNH, ɗ); Est. Amazonas, S. Paulo Olivenci, VIII.1913, H. C. Boy ( FMNH, 1?); no locality data ( BMNH, ɗ); Pará, Jacaréacanga, XII.1968, M. Alvarenga ( AMNH, Ψ); Uypizanga, Rio Negro, 14 km From Manaus, Amazonas, 300 ft, XII.1941, A. Rabaut ( AMNH, ɗ); Teffe, II.1915 ( AMNH, ɗ); Manaus, Amazonas, X.1945, W. Praetorius ( AMNH, 1?); no locality data, Bowring ( BMNH, 1?); Mauacamari, Bosque secundario, 30.VI.1990, C. Reyes ( USNM, Ψ); Para, Baker ( USNM, Ψ). FRENCH GUIANA: Cayenne, 42.i.S, Leach ( BMNH, Ψ). PERU: Quincemil, 1–16.XI.1962, L. Peña ( FMNH, ɗ); Madre de Dios Depto., Tambopata, 23.X.1982, ex mushrooms & litter, E. Watrous & G. Mazurek ( FMNH, ɗ); Itaya, Rio Itaya, E. Le Moult ( BMNH, 1?); Iquitos, 29.X.1927 ( AMNH, 1?); Dept. Loreto, 1.5 km N Teniente López, 2°35.66’S, 76°06.92’W, 210–240 m, 22.VII.1993, R. Leschen, ex: general collecting ( SEMC, 1 ɗ).

Diagnosis. Total length 19.0– 22.4 mm; head, pronotum and elytra blue or metallic violet, with metallic green reflections; abdomen dorsally red, with golden, blue or violet reflections, or golden with different metallic reflections; abdominal visible segments 5 and 6 metallic, and different in color from remaining segments; head rounded, 1.23–1.37 times as long as wide, moderately wider than pronotum (0.98–1.16 times), dorsally and ventrally convex, ventrally with moderately dense, expanded, umbilicate punctures (10–19 in each half of head), arranged in “v” (similar to Fig. 50 ); apical antennomere in males moderately oblong (length/width: 1.30–1.45) and almost as long as antennomeres 9+10 combined (1.00–1.06 times; Fig. 26 ); mandibles without basal external channel; pronotum ca. 1.5 times as long as wide (length/width: 1.36–1.46), shorter than elytra (0.76–0.83 times their length), with two clearly visible depressed areas in posterior third ( Fig. 56 ); prosternum moderately transverse (length/width: 0.70–0.82); aedeagus ovate, length 2.0– 2.3 mm, with parameres long (0.50–0.56 times as long as median lobe), apical area of median lobe 0.38–0.40 times as long as the total length of median lobe, and internal sac moderately visible ( Fig. 82 ).

Variation. Males have the head dorsally more convex than females, the mandibles do not have a basal external channel (occasionaly reduced), and the upper line of pronotal hypomeron may be partially or completely absent in anterior third or completely developed.

Comparative notes. Based on the revision of the holotypes, P. magnificus ( Bernhauer, 1911) is a junior synonym of P. i g n e u s ( Fauvel, 1901). The red, metallic coloration of the body (or part of it) of this species and P. splendens permits easy separation from the remaining species of the genus. They can be distinguished because P. i g n e u s has a rounded, dorsally and ventrally convex head, with antennomeres 4–10 transverse, and the aedeagus ovate, whereas P. splendens has rectangular, dorsally and ventrally flat head, with antennomeres 4–8 transverse, antennnomeres 9–10 nearly as long as wide, and the aedeagus pear-shaped.

Geographical distribution. French Guiana, Peru (first national records), and Brazil ( Herman 2001).

Figures

FIGURES 48 – 53. Cephalic ventral view: 48, Renda flagellicornis; 49, Philonthus testaceipennis; 50, Plochionocerus simplicicollis; 51, P. gracilis; 52, P. h e r m a n i; 53, P. puncticeps.

FIGURES 20 – 31. Antennae: 20, Philonthus testaceipennis; 21, Renda flagellicornis; 22, Agrodes conicicollis; 23, A. elegans; 24, Plochionocerus gracilis; 25, P. humeralis; 26, P. i g n e u s; 27, P. m a rq u e z i; 28, P. puncticeps; 29, P. re t i c u - laris; 30, P. s p l e n d e n s; 31, P. transversalis.

FIGURES 54 – 62. Pronotum: 54, Philonthus testaceipennis; 55, Renda flagellicornis; 56, Plochionocerus simplicicollis; 57, P. reticularis. Elytra: 58, Agrodes spp.; 59, Plochionocerus spp. Midleg: 60, Philonthus testaceipennis; 61, Agrodes spp.; 62, Plochionocerus spp.

FIGURES 79 – 87. Ventral (left) and lateral (right) view of aedeagus: 79, Plochionocerus fulgens; 80, P. h e r m a n i; 81, P. humeralis; 82, P. ig neu s; 83, P. impressipennis; 84, P. janthinus; 85, P. marquezi; 86, P. modestus; 87, P. newtonorum. Scale bar 1 mm.